An aim of this research is to examine the effects of enhances secretory antibody directed to glucosyltransferase (GTF) on plaque and dental caries. Studies in hamsters will determine the effect of local immunization with S. mutans GFT on infection with S. sanguis. Enzume linked imuunosorbent assay (ELISA) will be used for secretory antibody determinations to GTF. Studies of the secretory IgA response to GTF will also involve modes of enhancing the response with adjuvants. Various orally active adjuvants will be tested in combination with GTF. Cellular aspects of secretory IgA response will be tested with GTF as antigen. A plaque forming cell assay for GTF will be developed. Cell transfers and antibody-forming cells in organs will be monitored with an ELISA technique with cells in culture. Studies of the role of the T cell in the secretory immune response will be pursued in in vivo reconstitution experiments with thymus cells. Also the effects of enhanced secretory immunity (adjuvants) and the effects of T cell deprivation on dental caries will be studied. The long term goals of this proposal are to increase understanding of the secretory immune response so that this reponse could most effectively be utilized to combat dental infections. Also it is particularly important to optimize the effectiveness of GTF as a vaccine administered orally or by injection. Immunological and microbiological methodology will be employed in order to facilitate the development of a vaccine effective against dental caries.